1. Field of the Invention
The present invention relates to a data sink for receiving data coming from the outside thereof through an interface.
2. Description of the Prior Art
Conventional systems for receiving data from a host computer through an interface include the interruption method and the received data monitoring method.
In the interruption method, specific hardware for generating interruptions is used when the data sink receives data. During an interruption the data sink executes a data receiving procedure.
On the other hand, in the received data monitoring method, a data receiving processor itself periodically monitors to determine whether or not received data have arrived therein, and starts data receiving processing if data have arrived at the time of monitoring.
In an application of the interruption method, a receiving controller which works as an interface generates an interruption using specific hardware to enable the receiving controller to start data receiving processing. Consequently, in the processing by the receiving controller, waste of time can be minimized, resulting in improved processing efficiency. However, since specific hardware for generating interruptions is required, circuit construction is complicated, resulting in a cost increase. For those reasons, the specific hardware has been included in comparatively high-grade equipment.
On the contrary, in comparatively low-grade equipment the above-mentioned received data monitoring method of monitoring the arrival of data received in a predetermined period is employed. There is no problem if a period used for monitoring happens to accord with a period in which data is transmitted from a host computer, but if the two periods are different from each other defects arise, such as lowering of processing efficiency in the receiving controller which lowers the throughput in receiving data.